Evidence from several investigators suggests that BRA are present in a spectrum of antigenic specificities in Alzheimer's Disease (AD) and provide conceptual support for their pathogenetic role. Endogenous BRA will be demonstrated by direct immunohistochemical staining of AD and control brain tissue from the rapid autopsy protocol (RAP) of Duke University, Serum titers of BRA will be determined by Western blot of human brain homogenate. Regional distribution of autoantigenic specificities will be demonstrated by indirect immunohistochemical staining of RAP brian tissue and normal young adult brain tissue using AD and aged control sera. Previous work by the PI in collaboration with Roy Walford, M.D. has demonstrated that lymphoblastoid cell lines (LCL) from individuals secreting high titer antibodies may be used to created human- human hybridomas secreting antibodies of desired specificity which can be purified and characterized. This technique will be used to develop human monoclonal BRA which can be exploited to characterize the spectrum of antigenic specificities in AD and normal aged by immunoblot, tissue distribution, blocking and cytotoxicity studies. The Alzheimer's Disease research Center at Duke, directed by Allen Roses, M.D., offers a unique resource for investigation of molecular immunological mechanisms in the pathogenesis of AD. The tissue obtained through the RAP is invaluable to this endeavor. In addition, the Center has available LCLs and serum from several pedigrees of late onset AD. This material is the core of Dr. Roses' investigation of the molecular genetics of AD. In order to round out my training during this award period, I will become trained in the molecular genetic techniques in routine use in Dr. Roses' laboratory. My aim will be to use human monoclonal BRA to unique epitopes, for screening of a human brain with cDNA expression library so that purified antigen is available for further studies.